Improve type specifications and documentation

- Added missing type specifications for Hello function and rules - Updated documentation for the Deserialize protocol -
Cleaned up IBAN validation function documentation - Enhanced test fixture generation with clearer parsing and error
messages

lib/iban_ex/country/template.ex

@@ -9,7 +9,7 @@ defmodule IbanEx.Country.Template do
 
   @callback size() :: size()
   @callback rule() :: rule()
-  @callback rules() :: []
+  @callback rules() :: keyword()
   @callback rules_map() :: %{}
   @callback bban_fields() :: [atom()]
   @callback bban_size() :: non_neg_integer()
@@ -66,7 +66,7 @@ def bban_fields(), do: rules_map() |> Map.keys()
       def rules_map(), do: rules() |> Map.new()
 
       @impl IbanEx.Country.Template
-      @spec rules() :: []
+      @spec rules() :: keyword()
       def rules() do
         {rules, _bban_size} = calculate_rules()
         rules

lib/iban_ex/deserialize.ex

@@ -1,4 +1,10 @@
 defprotocol IbanEx.Deserialize do
+  @moduledoc """
+  Protocol for converting various data types into IBAN structs.
+
+  Implementations exist for String, Map, and List types.
+  """
+
   @type iban() :: IbanEx.Iban.t()
   @type iban_or_error() ::
           iban()
@@ -15,13 +21,8 @@ def to_iban(value)
 defimpl IbanEx.Deserialize, for: [BitString, String] do
   alias IbanEx.{Parser, Error}
   @type iban() :: IbanEx.Iban.t()
-  @type iban_or_error() ::
-          iban()
-          | {:invalid_checksum, binary()}
-          | {:invalid_format, binary()}
-          | {:invalid_length, binary()}
-          | {:can_not_parse_map, binary()}
-          | {:unsupported_country_code, binary()}
+  @type iban_or_error() :: iban() | {atom(), binary()}
+
   def to_iban(string) do
     case Parser.parse(string) do
       {:ok, iban} -> iban

lib/iban_ex/parser.ex

@@ -9,17 +9,12 @@ defmodule IbanEx.Parser do
   @type check_digits_string() :: <<_::16>>
 
   @type iban() :: IbanEx.Iban.t()
-  @type iban_or_error() ::
-          {:ok, iban()}
-          | {:invalid_checksum, binary()}
-          | {:invalid_format, binary()}
-          | {:invalid_length, binary()}
-          | {:can_not_parse_map, binary()}
-          | {:unsupported_country_code, binary()}
+  @type iban_or_error() :: {:ok, iban()} | {:error, atom()}
 
   @spec parse({:ok, binary()}) :: iban_or_error()
   def parse({:ok, iban_string}), do: parse(iban_string)
 
+  @spec parse(binary(), keyword()) :: iban_or_error()
   def parse(iban_string, options \\ [incomplete: false])
 
   def parse(iban_string, incomplete: false) do
@@ -70,6 +65,7 @@ def parse(iban_string, incomplete: true) do
   end
 
   @spec parse_bban(binary(), <<_::16>>) :: map()
+  @spec parse_bban(binary(), <<_::16>>, keyword()) :: map()
   def parse_bban(bban_string, country_code, options \\ [incomplete: false])
 
   def parse_bban(bban_string, country_code, incomplete: true) do

lib/iban_ex/validator/validator.ex

@@ -101,7 +101,7 @@ defp size(iban) do
     |> String.length()
   end
 
-  # - Check whether a given IBAN violates the required format.
+  @doc "Check whether a given IBAN violates the required format."
   @spec iban_violates_format?(String.t() | nil) :: boolean
   def iban_violates_format?(nil), do: true
 
@@ -119,21 +119,21 @@ def iban_violates_format?(iban) when is_binary(iban) do
     has_invalid_chars or country_code_lowercase
   end
 
-  # - Check whether a given IBAN violates the required format in bank_code.
+  @doc "Check whether a given IBAN violates the required format in bank_code."
   @spec iban_violates_bank_code_format?(binary()) :: boolean
   def iban_violates_bank_code_format?(iban), do: iban_violates_bban_part_format?(iban, :bank_code)
 
-  # - Check whether a given IBAN violates the required format in branch_code.
+  @doc "Check whether a given IBAN violates the required format in branch_code."
   @spec iban_violates_branch_code_format?(binary()) :: boolean
   def iban_violates_branch_code_format?(iban),
     do: iban_violates_bban_part_format?(iban, :branch_code)
 
-  # - Check whether a given IBAN violates the required format in account_number.
+  @doc "Check whether a given IBAN violates the required format in account_number."
   @spec iban_violates_account_number_format?(binary()) :: boolean
   def iban_violates_account_number_format?(iban),
     do: iban_violates_bban_part_format?(iban, :account_number)
 
-  # - Check whether a given IBAN violates the required format in national_check.
+  @doc "Check whether a given IBAN violates the required format in national_check."
   @spec iban_violates_national_check_format?(binary()) :: boolean
   def iban_violates_national_check_format?(iban),
     do: iban_violates_bban_part_format?(iban, :national_check)
@@ -150,7 +150,7 @@ defp iban_violates_bban_part_format?(iban, part) do
     end
   end
 
-  # - Check whether a given IBAN violates the supported countries.
+  @doc "Check whether a given IBAN violates the supported countries."
   @spec iban_unsupported_country?(String.t()) :: boolean
   def iban_unsupported_country?(iban) do
     supported? =